Whats your favourite book and why?

[Thumpalumpacus]

 His writing is riveting but entirely wasted on junk themes.

I'd disagree. It was nominally about an extraterrestrial terrorizing a region, but the underlying theme -- of youth lost and recaptured -- while perhaps not original, is handled with an interesting plot, and certainly something we all consider on occasion. The Stand as well, with its theme of loss and redemption, is great too, for my money.